Chasse Brunet will be closed to through-traffic from Monday 10th December.
The rat-run links St Saviour's Hill with Bagatelle Road and is used regularly by students walking to and from St Saviour's Primary School, Grainville and FCJ Primary School. There's no pavement on the road.
The closure is a year-long trial to improve the safety of the road and encourage walking and cycling to school.
A barrier gate will be built just north of the access to Langtry Gardens, so that residents continue to have access and vehicles are able to turn around.
The closure was the most popular option at a "well-attended" community meeting.
Emergency vehicles and refuse trucks will still have access.